Acquired immunodeficiency syndrome (AIDS) is a serious immunodeficiency disease caused by infection with AIDS virus, i.e., human immunodeficiency virus (HIV). Because of its extremely high risk of death, there is a pressing social need for countermeasures, but no effective therapeutic modality or vaccine has been developed as yet. The only known anti-AIDS virus agent that has been approved by the Food and Drug Administration of the United States is azidothymidine (AZT). However, this drug has not only high toxicity but has the drawback that repeated administration over one year results in development of resistance to AZT in AIDS virus. Therefore, the advent of a more useful therapeutic agent has been keenly demanded (Science 249, 1533-1543 (1990)).
The present inventors have conducted the extensive investigations to solve the above problems and found that cepharanthine is useful as an active ingredient in an anti-AIDS virus composition. The present invention has been accomplished based on such findings.